What Is Microbial Enhanced Oil Recovery?

Enhanced Oil Recovery ( EOR ) technology is directed to the injection of oil displacement agents or profile modifiers in reservoirs, to improve the physical and chemical characteristics of reservoirs and reservoir fluids, to improve macroscopic spillover efficiency and microscopic displacement efficiency. Oil recovery methods are collectively referred to as enhanced oil recovery technologies, or " enhanced oil recovery technologies ". Enhanced crude oil recovery is also known as tertiary recovery (as opposed to primary and secondary recovery). According to the US Department of Energy, EOR has three main technologies: heat recovery, gas injection, and chemical injection. Sometimes the term quaternary recovery is used to refer to more advanced, speculative EOR techniques. With EOR, 30% to 60% or more of the original oil in the reservoir can be extracted, while primary and secondary recovery ratios are 20% to 40%.

There are three main technologies for enhanced oil recovery: gas injection, thermal injection, and chemical injection. In the United States, natural gas, nitrogen, or carbon dioxide (

The natural gas injection volume of other gases accounts for nearly 60% of the EOR output. Thermal injection involves the generation of heat, which accounts for 40% of EOR production in the United States, most of which occurs in California. Chemical injection may involve the use of long-chain molecules called polymers to increase the effectiveness of water injection, which accounts for about 1% of US EOR production. In 2013, the United States introduced a technology called Plasma-Pulse from Russia. This technology can increase existing well production by another 50%.

• Elevated production wells typically pump large volumes of produced water to the surface. This water contains

  China's oilfields have low waterflooding recovery rates, and the comprehensive water content of eastern oilfields is already very high. They have generally entered a stage of diminishing oilfield development and production.In recent years, most of the difficult-to-recover reserves of low-permeability and high-viscosity oilfields have been discovered. It has become an urgent strategic task for the sustainable development of the onshore oil industry. In 1998, three secondary evaluations of oil recovery potential were carried out nationwide. Petroleum geological reserves suitable for gas injection () miscible or immiscible flooding accounted for more than 10% of the participating evaluations, and the rough average recovery rate was 16.4%. The evaluation results also show that there are nearly 400 million tons of low-permeability oil reserves in China that are difficult to inject and develop. ^[1]

  The basic theories of M EOR's domestic and foreign research status, methods, strains and nutrient solution preparation, reservoir screening standards, mechanism of action, and mine field application are discussed. Based on the comparison of the three oil recovery technologies such as the three-component complex flooding, the good development prospects of MEOR are clarified. ^[2]